Pocket bike chamber pipe

[Trafficjamz]

On the spree


I have really only made it louder. But the "looks cool" factor has gone up a bit.

[fightingplankton]

no increase in performance?

[Trafficjamz]

no increase in performance?

Hard to tell. There is no decrease in performance.

Sounds like a dirtbike.

[fightingplankton]

reason i ask is i have that old rusty expansion chamber off that little minibike i found at my grandpa's and i dont want to F up my muffler if it isnt going to gain me anything.

[mustangwagz]

I have really only made it louder. But the "looks cool" factor has gone up a bit.

Sounds like a dirtbike.

Looks like ill have to find me one!! lol Loud and Burly soundin is MY STYLE!! lol

[elitedio]

How much did you change the jetting?

One thing to keep in mind is that the head pipe is probably too long and the pipe too short. I would cut off a couple of inches the stock head pipe and move the expansion chamber further forward. I went through this on my conversion. I am sure that you have done it but get a rear mount on it before you ride it.

Nice conversion.

no increase in performance?

Hard to tell. There is no decrease in performance.

Sounds like a dirtbike.

[Trafficjamz]

How much did you change the jetting?

One thing to keep in mind is that the head pipe is probably too long and the pipe too short. I would cut off a couple of inches the stock head pipe and move the expansion chamber further forward. I went through this on my conversion. I am sure that you have done it but get a rear mount on it before you ride it.

Nice conversion.

I did not change the jetting at all

I did not weld the rear bracket because I figured I would need to change it several times.

Any actual measurements or caculations that would help?

[elitedio]

Too many variables to say exactly. Have you read the jennings book? it is old but is available online here.

Step one would be to up the jetting to prevent you holing the piston.

Step two make some sort of mount to test, your flange is not designed to take the weight.

Your system has a rather long head pipe and is rather short pipe. You can make it work.

[Trafficjamz]

Too many variables to say exactly. Have you read the jennings book? it is old but is available online here.

Step one would be to up the jetting to prevent you holing the piston.

Step two make some sort of mount to test, your flange is not designed to take the weight.

Your system has a rather long head pipe and is rather short pipe. You can make it work.

I am re-designing this pipe to be a little shorter and to be quieter.

I will end up using it on a big bore spree (44mm.), so the carb on that, will already be upjetted.

Maybe I'll use some heatduct strapping to help support the pipe when I test it.

[elitedio]

Not a bad idea, I cut off and rewelded my strap several times.

Maybe I'll use some heatduct strapping to help support the pipe when I test it.

[ae86guy]

as did i i cut and welded heaps but i also experimented with different shaped chambers to see what the difference was got one on there now that works good i wouldnt say perfect i want to make a new header pipe from the jug down and loose the two 90. bends the factory pipe has